Currently, scientists believe the world's largest garbage dump isn't on land...it's in the Pacific Ocean. The Great Pacific Garbage Patch stretches from the coast of California to Japan, and it's estimated to be twice the size of Texas. "This is the most shocking thing I have seen," Oprah says.

To give you a little background: Years of bottles, bags, toys, packaging and plastic trash from all corners of the Earth are swirling in a plastic whirlpool in the North Pacific. Discarded water bottles from Iowa, takeout containers from New York City, flip-flops from California and plastic debris from the world over make their way from land into storm drains, streams, rivers and other waterways. They are carried out sea, where they get trapped in swirling ocean currents - forming a giant, floating trash dump of an enormous proportion - no matter how you quantify it.

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What can you do about it? Well, as Kate wrote, you can be sure to recycle your plastic! And you can use less plastic.